This study examined the usefulness of radiotelemetry for estrous detection in buffalo heifersand the impact of prostaglandin F2(PGF2) administration during the early or late lutealphase on estrous behavior and ovulatory follicle variables. Induction of estrus with PGF2at a random stage of the estrous cycle was followed by the arbitrary division of heifersinto groups receiving a second dose of PGF2during either the early (n = 33) or late (n = 17)luteal phase (6–9 or 11–14 days after estrus, respectively) for the induction of synchronizedestrus. The electronic detection of synchronized estrus by radiotelemetry was confirmedusing ultrasonography every 6 h until ovulation. Radiotelemetry was 90% efficient and 100%accurate for estrous detection. Intervals between the PGF2dose and the beginning of syn-chronized estrus (40.7 ± 10.9 vs. 56.7 ± 12.8 h) or ovulation (70.0 ± 11.3 vs. 85.6 ± 12.5 h)were shorter (P < 0.05) for heifers receiving PGF2during the early luteal phase. PGF2administration during the early or late luteal phase produced similar (P > 0.05) results forthe duration of estrus, the intervals from the beginning or end of estrus to ovulation, thenumber and duration of mounts per estrus, the duration of mounts, the diameter of the ovu-latory follicle and the luteal profile on day 5 after estrus. In conclusion, radiotelemetry wasa suitable tool for the efficient and accurate detection of estrus in buffalo heifers. Treatmentwith PGF2during the early luteal phase had a shorter interval to synchronized estrus andovulation; however, estrous behavior, ovulatory follicle dynamics and subsequent lutealactivity were similar following PGF2administration during the early or late luteal phase.© 2014 Elsevier B.V. All rights reserved.